Cork-cutting machine



H. G. MONKHORST.

CORK CUTTING MACHINE. APPLICATION FlLED muzs. 1919.

Patented Oct. 3, 1922.

mmm e 6 SHEETSSHEET I.

/17 van for.

flcrmanw' fiamrduS/VMk/mm/ H. G. MONKHORST.

CORK CUTTING MACHINE. APPLICATION FILED JULYZS. I919.

1&30329. v Patented 00. 3, 1922.

6 SHEETSSHEET 3.

o, 0 64 72 a a myeflfoi" H. a. MONKHORST. CORK CUTTING MACHINE. APPLI CATION FILED JULY25,v19I 9 Patented Oct. 3, H22.

6 SHEETS-SHEET 2.

KAMLEQQ.

[Zulu/111 V //7 van for H. G? MGMI'GIORSTa CORK CUTTING MACHINE. APPLICATION man JULY25, 1919.

Pabs'med Oct 3, 1922.,

6 SHEETS-SHEET 5.

' Mvenfar ficrmanusfiamrdusMmk/mm? H. G. MONKHORST. CORK CUTTING MACHINE. APPLICATION FILED sunzs. I919.

Patented 0%. 3,1922 5HEETu-SHEET 6 Patented @et. 3, i922.

HERMAN'US GERARDUS MONKHORST, OF DELFT, NETHERLANDS.

CORK-CUTTING IIIACHINE.

Application filed July 25, 1919.

To all Q0/1077} it may concern Be it known that I, l-lnmmrros Gmnrnnos liloxki-ionsr, a subject of the Queen of the Netherlands, residing at Delft, Netherlands, have invented certain new and useful limproveinents in Cork-Cutting Machines, of which the following is a s 3e'cification.

In the manufacture of corks, suitably sized sheets of cork-tree bark are cut into strips of the required thickness, and the strips are divided into substantially prismatic pieces (the so-called quarters) which are given the desired shape in a cork cutting machine.

Dividing the sheets into strips and quarters cannot be done uiechanically, as corktrce bark hasi'iuinerous cavities, rents and flaws, especially at the back side, i. e., that side of the bark which on the tree was outside; seeing that the presence of these cavitics, etc, unfarorably affects the value of the corks, it is essential for the strips and the quarters to be cut in such a manner as to possess as few of these defects as possible, and it will be readily l'lnderstood that this operation can only be carried out manually by skilled workmen.

Cutting the piarters into corks is sometimes done entirely automatically, that is to say the quarters are mechanic: lly placed in a suitable machine which imparts a rotary motion to them, after which a reciprocating or rotary knife moving: along the quarter is the work )iece into'the shape of a cyhnoer or of a t icated cone, These automatic machines, however, have not adieu, satisfattiou, the reason being that the back side of the quarters presents more cavities, etc, than the front side, so that it is essential for the manufacture of superior corks that the depth of the cut-on theback of the quarter be greater than on the front; therefore, the work pieces should he placed somewhat cccentrically in the machine,depciiijicut upon the nature of the individual quarters, and it is clear that this cannot be done me hanicall} but requires considerable skill on the part of the operator.

A widely used machine 0;: ti type in which the quarter is manually placed between the chucks comprises a knife adapted to he moved by hand to and fro along t e work piece, said knife thereby imparting Serial No. 313,409.

rotary motion to the spindle of one of the chucks between which the quarter is gripped, in such a manner that the rotary speed of the work piece is. proportionate to the linearv speed of the knife. In these machines the knife is first moved in a given direction along thework piece, thereby taking off a cutting of a certain thickness,

whereupon it is returned into its original position and again driven alone; the cork at a slightly less distance from the axis of rotation, so that a second cutting is taken off and the workn-piece receives its final form. Owing to the rotary motion of the quarter being derived directly from the rectilinear motion of the knife, the latter is operative only during its motion in the one direction, for during its reverse motion that side of the work-piece which faces the knife moves in the direction from the back to the cutting edge of the tool, so that no material can be taken oil. This known machine has the disadvantageous feature that the corks therein cannot be cut to a true cylindrical or conical shape, for cork-tree bark contains numerous exceedingly hard portions, the so-called stones, which it is only possible to cut in one predetermined direction. If therefore a stone is so situated with respect to its grain as to resist the action of the knife during the operative stroke of the tool, it forms a projection on the finished cork which, on this account, is of inferior quality.

Now, according to the present invention, which has for its object to avoid said inconvenience, the knife is operative both duri115;- its outward and its inward rectilinear stroke along the work-piece which during this'operation. turns in an invariable direction. Preferably the machine should be so constructed that the driving spindle of the work-piece 1S uncoupled from its driving gear some time before the end of each stroke of the knife, and again coupled therewith some time after the beginning of said strokes. Owing to this construction the work-piece may be rotated at constant speed during the time the sinusoidally varying arectilinear speed of the knife exceeds a given value, and be stopped as soon as the speed of the tool falls below said value. it should be noticed that the rotary motion of the work-piece should be interrupted at the moments stated. as otherwise the workpiece rotating at high speed would move against a knife having too low a speed whereby the material might partly be rolled up instead of being properly cut.

In the annexed drawing, which illustrates an embodiment of the invention:

Fig. 1 is a side elevational view and Fig. 2 an end view of the machine;

Fig. 8 is a longitudinal sectional view of the spindle carrier or turret of the machine illustrated in Figs. 1 and 2, and

Fig. 4 is a sectional view of the knife holder with associate parts.

.liig. 5 isa side elevation and Fig. 6 a plan view of the mechanism to withdraw the pawl 92;

Fig. (7 shows the knifeholder 14 with its re essed portion 33 in the bottom in perspective'.

In the example shown the machine comprises a frame 1 with bearings 4 for the main shaft to which rotary motion with constant speed may be imparted by a pulley 3. Keyed on the iaft 2 is a crank 5 adapted through a connecting rod 6 to impart swinging motion to a lever 8 secured to a shaft 7. The rod 6 and the crank 5 are connected by a crank pin 9 secured to the rod and passing through a slot 10 in the crank in which it may be locked by a nut, whereby the length. of stroke of lever 8 may be adjusted. The free end of lever 8 is pivoted at 11 to one end of a rod 12, the other end of which is pivoted at 13 to a knife holder 14, see Figs. 4 and 7.

As shown in Figs. 4 and 7, the knife holder consists of a rigid member of suitable length, to which the knife 15 is secured by means of a cover plate 16 and screws 17, and the back side of which is provided with a V-shaped groove engaging a suitably sectioned guide bar 18; caps 19 having corre sponding J-shaped grooves and bolted to the holder 14 serve to secure the latter to the bar 18. it being understood that the holder has freedom of sliding motion along the bar 18 without appreciable friction. The guide bar 18 is not'rigidly secured to the frame, but rotatably supported by centres 20, 21, a roller 22 mounted on a stud 23 of a bracket 24 supporting the holder 14 with the knife 15 in a substantially horizontal position.

The bracket 24 has two slotted tongues 26 for receiving locking bolts 27, 28 by means of which the bracket 24 may be secured to the frame in the required position. The adjustment of the bracket 24 with associated parts is facilitated by the provision of vertical bolts 29. 3O screwed through eyes 81, 32 cast on the frame. After the locking bolts 27, 28 are released the bracket 24 may be given the desired angular position by properly turning the adjusting bolts 29, 30, after which it may be locked by tightening the bolts 27', 28.

The bottom face of the knife holder 14 has a recessed portion 83 running longitudinally from its rear end to the middle and which alines with the roller 22, so that when the knife 15 has reached the middle of its outward stroke (in Fig. 1 to the right) the said roller 22, which supports the knife holder 14, will travel along this recessed portion, with the result that said holder drops or falls through a slight distance whereby the knife during the second half of said stroke moves at a somewhat lower level than during the first half. In other words, during its outward stroke the knife 15 will first take off from the quarter a cutting of predetermined thickness, and thereafter a second cutting, so that at the end of said stroke the work piece has received its final shape.

The main shaft 36 of what may be termed the revolving head or turret is supported in bearings of the frame 1 and adapted to be intermittently rotated by the chain wheel 37 keyed thereon. The turret, shown in detail in Fig. 3, comprises a disc 38 secured to the right hand end of main shaft 36 and provided with four holes spaced 90 apart to receive spindles the left hand ends of which are supported in bearing brackets fixed to a block 43. The said. spindles, each of which carries at its left hand end a chuck 39, are of two-part formation, and comprise a rod 40 slidably mounted in a sleeve 41 but secured against rotation therein. The said sleeve 41, which is rotatably mounted in disc 38 and whose end thrust is taken up by a suitable hearing, has a friction socket 42 secured to its right hand end extending beyond the disc 38.

The block 43, which is slidably mounted on the main shaft 36 but secured against rotation thereon, has four triangular section longitudinal grooves, spaced 90 apart and each receivinga slide 44. Each slide 44 has a hole at its left hand end, and adjustably mounted in this hole is a bracket 45 supporting a rotatable chuck 46 adapted to be set in alignmentwith the spindle 40, 41, a clamping screw 47 serving to lock the bracket 45 in its proper position.

At its right hand end each slide has a cylindrical portion passing through the hole in a flange 48 secured to the main shaft 36 of the turret, said cylindrical portion having at its left hand end a collar which when contacting with the left hand face of the flange 48 prevents further movement to the right of the slide by the action of a coiled spring 49 secured to a sleeve 50. The said sleeve 50, which is free to slide axially on he main shaft 36 but prevented from rotating thereon, is externally threaded whereby itmay be axially displaced by 1 ,asonee meansof a cap 511 lockedagainst axial move ment by a collar integral with the main shaft, and by a ring 52 secured to said shaft.

The cap 51 permits of all springs 4 .9 to be simultaneously tightened and released.

As previously stated, the block 4-3 is slidably mounted on the main shaft 36, a clamping screw 53 serving to lock said block in the required position, whereby the distance between the chucks 39 and 456 may be adjusted.

At its left hand end each slide 44 has a re cess or notch 54, the purpose of which will be stated later.

To that spindle 4O, 41 which assumes its highest position (ic in Fig. l) rotary motion may be imparted by a friction cone 55 (see Fig. 11') provided at the rear end of the machine and secured on a spindle 56 which is rotatable in a sleeve 57 at the upper end of an arm 58, The lower end of arm 58 is formed by a horizontal fork 59 (see Fig. 2) rotatable about a shaft 60 (see Fig. l) supported. in bearings 61 and secured against rotation by set screws. Through a strap 62. the arm 58 is engaged by a coiled spring 63 secured to the frame and having a tendency to pull the arm 58 to the left (Fig. 1).

The fork 59 is provided with a lever 6% having a slot 65 receiving bolts 66, 67 for the connection of the right hand ends of rods 68, 69, the other ends of which are provided with elongatedeyes engaging pins 70, 71 on the ends of a double-armed lever 72 keyed on the shaft 7. The lengths of the rods 68, 69 and those of their eyes should be such that the lever 64 is moved through a short distance to the left at the end both of the inward and of the outward stroke of lever 8, whereby at such leftward movements of said lever 6f the arm 58 will be rocked or swung to the rigl'it, with the result that the friction cone 55 is withdrawn from the socket 42 with which it is normally held in engagement by the action of spring 63.

The spindle 56 carrying the cone 55 has keyed to its free end a chain wheel 73 to whichrotary motion may be imparted by a chain 74 thrown over a sprocket wheel 75 on a shaft 76 supported in av bearing formed by the forked lower end 59 of arm 58. The shaft 7 6 has secured to it a mitre pinion 7 7 meshing with a mitre wheel 7 8 which is loosely mounted on shaft 60 and rigidly connected with a sprocket wheel 7 9, driven by a chain 80 and a sprocket wheel 81 fast on the main shaft 2.

The turret receives intermittent rotary motion from a pneumatic driving gear comprising a cylinder 82 pivoted at 84': to the frame. and a piston to which reciprocating motion is imparted by a rod 88 pivoted to the lever 8. The. cylinder 82 is in communication by a tube 85 with a cylinder 86 whose piston rod87 is adapted to drive the turret. To this end the piston rod 87 (see Fig. 2) is connected with one. end of a chain 88, which passes over the chain wheel 37 on the shaft 36 of the turret and whose other end is secured to a coiled spring 89 fixed at 99 to the frame of the machine. The sprocket wheel 37 is a socalled free wheelwhich, when turning in a counter-clockwise direction with respect to Fig. 2, rotates the shaft 36, but which, when turning in opposite direction. by the action of spring 89, moves freely over and, hence, does not impart rotary motion to said shaft.

The disc 38 forming part of the turret has four peripheral notches 91 spaced 90? apart and formed as shown in Fig. 2. Said notches have for their duty to lock the turret whenever the friction socket 42 of one of the spindles ll), all registers with the friction cone 55, and for this purpose a spring loaded pawl 92 is provided arranged to be withdrawn from a notch 91 of disc 38 at the end of the inward stroke of lever 83. This withdrawal of the pawl 92 may be effected by engaging said pawl with a projection on a vertical spindle (Figs. 1, 5 and 6) which is rotated or turned at the proper moment through a certain angular distance by a crank 94eand a rod 95 pivoted to the frame, said rod 95 at its left hand end being pivotally connected to a pawl 95 which is pivoted at one end to the frame 1 and has its other end projecting into the path of a roller 8 mounted on an arm 8 pivoted to a bracket 8 adjustable on lever 8. The arm 8 is acted upon by a spring. The arrangement is such that when the lever 8 moves to the right the arm 8 swings to the left against the action of its spring and permits the roller 8 to move past the projecting end of the pawl 95 without effecting movement of the rod 95, hen, however, the lever 8 moves to the left, the roller 8 engages the end of the pawl 95 andmoves the rod 95 to the left, whereby. at theend of the movement of the lever 8 to the left, the pawl 92 is completely withdrawn from notch 91 and the piston in cylinder 86 is at such moment free to rotate the turret. Immediately thereafter the pawl. 92 by the action of its spring is again forced against the circiuuference of the disc 38 so that it again locks the turret as soon as the next notch 91 has come in line with said pawl.

A, pneumatic drive as described has the ad- 'vantz'eous feature that the power required for roating the turret is accumulated in the form of a vacuum in cylinder 89 during the whole leftward stroke of lever 8 and that it is suddenly transformed into kinetic energy by the cylinder 86 at the end of said stroke, so that the intermittent rotary motion of the turret is almost momentary. As a matter of course the same effect could be realized by a spring, but it is well known that springs which are continuously subjected to varying loads are liable to breakage.

A normally withdrawn pawl 96 which also coacts with the notches 91 of disc 38 is connected by a chain 98 to a handle 97 within the reach of the operator who, by turning said handle, may cause the pawl 96 to cute" one of the notches 91 and thereby stop the turret without shifting the belt onto the loose pulley.

Keyed on the shaft 7 is a second lever 99 having for its duty to withdraw at the proper moments and against the action of springs 19 the chucks e16 assuming the positions 7c and (Fig. For this purpose the lever 99 is pivoted to a rod 100 the left hand end of which carries a transverse member 101 having secured to it two rods 102 the ends of which are connected with chains 10 lpassing over uide Wheels 103. The chains 10 1 are connected with rods 105, 100, associated with spring loaded pawls 111, 112 by means of chains 107, 108 passing over wheels 109, 110. Said pawls 111, 112 are made to project into the recesses 54- of the intermittently rotating slides 14 in the positions 70 is, (Fig. 1), their springs always tending to draw them into their extreme right hand positions in which they are received by the said recesses The pawl 112 may also be actuated, i. e., moved to the left, by means of a handle 113, see Fig.2.

The operation of the mac lows:

If the crank pin 9 moves from its erirrenfie left hand to its extreme right hai d (Fig. 1), the crank 99 is moved to i. and the pawls 111, 112 are pulled to the is This allows the finished cork asped be tween the lowermost chucks (position 70,, in Fig. 4:) to fall out of the machine, whilst the chucks in the position 13 (Fig. d) move from one another so that the operator may place a quarte between them and press it against the chuck secured to t is spindle 4:0, If now the crank pin 9 moves to the left, the pawls 111, 112 will move to the right by the action of their springs, thereby allowin the slides eng ed by them to resume their original posiuons d the quarter to be gripped between the chucks in the position 70 When the crank pin 9 has nearly reached its extreme left hand position, the pawl 92 is withdrawn from the recess in disc 38 by which it was engaged, so that the vacuum produced in cylinder 82 may act through the piston in cylinder 86 on the turret and cause same to rotate through 90, after which the turret is again locked by pawl 92. Owing to this rotation the quarter reaches the position 70 thus coming within the reach of knife 15.

As long as the knife 1 assumes its on treme left hand position (Fig. 1), the friciine is as foltion socket 42is disengaged by the cone 55, the rod 68 connected to the lever 72 has g 68. The moment, however, the speed ake oil a cutting of a given thickness from he quarter, during which time the knife Lolder 14, supported by the roller 22, moves along the guide ba 18.

after having moved through half of their "11 of stroke the knife holder 1 1 and the 15 descend through a slight distance owing to the recessed portion 33 engaging the roller 22, whereby a second cutting is taken oil from the quarter and the cork receives its final shape.

At the end of its outward stroke the knife 15 will move so slowly as to be unable to smoothly cut the workpiece which rotates at and the riot ion cone 55 withdrawn from the socket 12 owing to the rod 69 being moved to the left by the pin 71. 1t will thus be understood that during the last part of its outward stroke the knife 15 moves'along the stationary finished cork.

The moments: wherein the cone 55 is withdrawn from the socket 1-2 may be varied by adjusting the lengths of the rods 68 and 69 by means of tightening screws.

During the first part of the return stroke of the latnife 15 the cork is evidently stationary; as soon, however, as the knife moves at sufficient speed, the cork begins to rotate in the same direction as during the outward stroke of the tool, whereby the lat-- ter permi ted to smoothly cut off the stones which should not have been removed yet. After having moved through half of its length of stroke the knife ascends slightly, whereby the knife disengages the cork.

The now ready-cut cork 'is moved into the position 711,, by the next rotation of the turret, in which position it may be polished by a suitable arrangement not shown.

As stated above the angular position of ied the arm 58 against the, action of e knife 15 reaches a certain value, i. e.,

ts outward stroke the knife 15 will" now the knife 15 relative to the axis of rotation Having now particularly described and ascertained the nature of my present invent-ion and in What manner the same is to be performed, I declare that What I claim is:

1. In a cork cutting machine, the combination of a cutting tool; a Work-holding turret comprising a carrier disk and a plurality of holding devices connected thereto; a pneumatic drive for imparting an intermittent, step-by-step rotary movement to said disk; and means for imparting an inclependent rotary movement to each holding device in succession.

2. In a cork cuttingmachine, the combination of a cutting tool, means for reciprocating said tool in a substantially rectilinear path, a Work-holding turret comprising a plurality of pairs of relatively movable chucks, pneumatic means actuated by said tool actuating means for imparting an intermittent rotary movement to said turret to bring said pairs of chucks successively into operative relation to said tool, detent means for said turret, operating to prevent rotation thereof except at the end'of movement of said tool in one direction, and means for imparting independent rotary movement to one chuck of each successive pair when in said operative position.

3. In a cork cutting machine, the combination of a cutting tool, means for reciprocating said tool in a substantially rectilinear path, a work-holding turret comprising a plurality of pairs of relatively movable chucks, means for imparting an intermittent rotary movement to said turret to bring said pairs of chucks successively into operative relation to said tool, driving means for imparting independent rotary movement to one chuck of each successive pair when in said operative position, and means for disengaging said driving means from said chuck near the end of movement of said cutting tool in one direction and for engaging said driving means with said chuck after said cutting tool has begun its movement in the opposite direction.

4. In a cork cutting machine, the combination of a cutting tool, means for reciprocating said tool in a substantially rectilinear path, a workholding turret comprising a plurality of pairs of relatively movable chucks, means for imparting an intermittent rotary movement to said turret to bring said pairs of chucks successively into operative relation to said tool, driving means for imparting independent rotary movement to one chuck of each successive pair when in said operative position, and means for disengaging said driving means from said chuck near the end of movement of said cutting tool in each direction and for engaging said driving means with said chuck after said cutting tool has begun its movement in the opposite direction.

5. In a cork cutting machine, Work holding means, means for imparting rotation to said Work holding means, a guide rod, a knife-blade holder mounted for reciprocation on said guide rod, means for reciprocating said holder, said holder being also adapted to tilt about the axis of said guide rod, a knife-blade carried by said holder,

and an anti-friction roller engaging the under surface of said holder, the surface of said holder engaging said roller being so formed as to cause the cutting edge of the knife-blade to travel in different rectilinear paths during the reciprocatory movement of said holder.

In testimony whereof I affix my signature.

HERMANUS GERARIDUS MONKHURST. 

